[Process and results of constructing a deprivation index for the districts of Madrid and Barcelona, Spain].

BACKGROUND There are few economic indicators that take the neighbourhood as the unit of reference in our context. The aim of this article is to describe the process and results of secondary data collection and development of a deprivation index (DI) for the neighbourhoods of the cities of Madrid and Barcelona, discussing their utility for research on health inequalities. METHODS Initial DI conceptual framework contained different elements that characterize deprivation and for which we collected second-level variables. ID was adapted to the availability of variables and to the results of an exploratory analysis. Finally, a factor analysis was performed to validate the IP. We built a DI based on five dimensions for Madrid (economy, population and territory, housing, cars and demographics) and 4 for Barcelona (all except "demographics"). Neighbourhoods were grouped into quartiles according to their score for the DI (Q4: higher levels of deprivation). Premature mortality rates and premature mortality ratios adjusted by age were calculated for each quartile. RESULTS The IP explained 55% of the observed variability in the indicators for Madrid and 69% for Barcelona. Premature mortality rate in Madrid for Q1 was 1.65 per 10³ in men and 0.92 per 10³ women and 2.81 per 10³ in men and 1.22 per 10³ in women residing in Q4. In Barcelona, the mortality rate was 2.33 per 10³ men and 1.15 per 10³ women in Q1 and 3.49 per 10³ in men and 1.52 per 103 in women living in Q4. CONCLUSION Premature mortality rates showed higher premature mortality in the most deprived districts.